The myth of the fingerprint as reliable forensic evidence
Our view is that taken as a whole, forensic evidence as used by prosecutors is inherently untrustworthy. For example, for years many people went to prison on the basis of the claims of a North Carolina anthropologist, Louise Robbins. She helped send people to prison or to Death Row with her self-proclaimed power to identify criminals through shoe prints. As an excellent recent Chicago Tribune series on forensic humbug recalled, on occasion she even said she could use the method to determine a person’s height, sex and race. Robbins died in 1987, her legacy compromised by the conclusion of many Appeals Courts that her methodology was bosh. There have been similarly hollow claims for lip prints and ear prints, all of them invoked by their supporters as “100 per cent reliable” and believed by juries too easily impressed by passionate invocations to 100 percent reliable scientific data.
Of course the apex forensic hero of prosecutors, long promoted as the bottom line in reliability–at least until the arrival of DNA matching–has been the fingerprint.
Fingerprints entered the arsenal of police and prosecutors in the late nineteenth century, touted as “scientific” in the manner of other fashionable methods of that time in the identification of supposed criminals, such as phrenology. A prime salesman was Francis Galton, Charles Darwin’s cousin and a founding huckster for the bogus “science” of eugenics. Actually fingerprints, at least in modern times, found their original use in the efforts of a British colonial administrator to intimidate his Indian laborers (whose faces he could not distinguish) from turning up more than once to get paid. He’d make a great show of scrutinizing the fingerprints he insisted they daub on his ledger book.
Then, as now, the use of the so-called “unique fingerprint” has been histrionic, not exactly scientific. In 1995, so the Chicago Tribune series discovered, “one of the only independent proficiency tests of fingerprint examiners in U.S. crime labs found that nearly a quarter reported false positives, meaning they declared prints identical even though they were not–the sort of mistakes that can lead to wrongful convictions or arrests.”
Decade after decade people have been sent to prison for years or dispatched to the death cell, solely on the basis of a single, even a partial print. So great is the resonance of the phrase “a perfect match” that defense lawyers throw in the towel, as judge and jury listen to the assured conclusions of the FBI’s analysts who virtually monopolize the fingerprint industry in the U.S.A. Overseas, in London’s Scotland Yard for example, the same mesmerizing “certainty” held sway, and still does.
In the U.S.A., part of the mystique stems from the “one discrepancy rule” which has supposedly governed the FBI’s fingerprint analysis. The rule says that identifications are subject to a standard of “100 per cent certainty” where a single difference in appearance is supposed to preclude identification.
The 1997 lab scandals threw a shadow over the FBI’s forensic procedures as a whole and the criminal defense bar began to raise protests against prosecutorial use of latent fingerprint identification evidence, as produced by FBI procedures. In 2002 Judge Louis Pollak, presiding over in a case in Pennsylvania, initially ruled that the FBI’s fingerprint matching criteria fell below new standards of forensic reliability (the Daubert Standards) stipulated by the Supreme Court. Ultimately the judge was persuaded that the FBI’s fingerprint lab had never made a mistake. In 2004, in U.S. v. Mitchell, the Third Circuit Court of Appeals upheld these same questionable procedures.
But in 2006, the FBI’s new inspector general, Glenn Fine, grudgingly administered what should properly be regarded as the deathblow to fingerprint evidence as used by the FBI and indeed by law enforcement generally.
The case reviewed by Inspector General Fine, at the request of U.S. Rep John Conyers and U.S. Senator Russell Feingold, concerns the false arrest by the FBI of Brandon Mayfield, a lawyer from Beaverton, Oregon.
On March 11, 2004, several bombs exploded in Madrid’s subway system with 191 killed and 1,460 injured. Shortly thereafter the Spanish police discovered a blue plastic bag filled with detonators in a van parked near the Acala de Heres train station in Madrid, whence all of the trains involved in the bombing had originated on the fatal day.
The Spanish police were able to lift a number of latent prints off the bag. On March 17 they transmitted digital images of these fingerprints to the FBI’s crime lab in Virginia. The lab ran the images through its prized IAFIS, otherwise known as the Integrated, Automated, Fingerprint Identification System, containing a database of some 20 million fingerprints.
The IAFIS computer spat out twenty “candidate prints”, with the warning that these 20 candidates were “close non-match”. Then the FBI examiners went to work with their magnifying glasses, assessing ridges and forks between the sample of 20 and the images from Spain. In a trice, the doubts of the IAFIS computer were thrust aside, and senior fingerprint examiner Terry Green determined that he had found “a 100 per cent match” with one of the Spanish prints of the fourth-ranked print in the IAFIS batch of 20 close non-matches. Green said this fourth ranked print came from the left index finger of Brandon Mayfield. Mayfield’s prints were in the FBI’s master file, not because he had been arrested or charged with any crime, but because he was a former U.S. Army lieutenant.
Green submitted his conclusions to two other FBI examiners who duly confirmed his conclusions. But as the Inspector General later noted, these examiners were not directed to inspect a set of prints without knowing that a match had already asserted by one of their colleagues. They were simply given the pair of supposedly matched prints and asked to confirm the finding. (These two examiners later refused to talk to the FBI’s inspector general.)
The FBI lost no time in alerting the Federal Prosecutor’s office in Portland, which initiated surveillance of Mayfield with a request to the secret FISA court, which issued a warrant for Mayfield’s phone to be tapped on the grounds, laid out in the Patriot Act, that he was a terrorist, and therefore by definition a foreign agent.
Surreptitious tapping and surveillance of Mayfield began. On April 2, 2004, the FBI sent a letter to the Spanish police informing them that they had developed a big break in the case, with a positive identification of a print on the bag of detonators.
Ten days later the forensic science division of the Spanish national police sent the FBI its own analysis. It held that the purported match of Mayfield’s print was “conclusively negative”. (The inspector general refered to this as the “Negativo Report”.)
The next day, April 14, the Federal Prosecutor in Portland became aware of the fact that the Spanish authorities were vigorously disputing the match with Mayfield’s left forefinger. But by now the Prosecutor and his team were scenting blood. Through covert surveillance they had learned that Mayfield was married to an Egyptian woman, had recently converted to Islam, was a regular attendee at the Bailal mosque in Portland, and had as one of his clients in a child custody dispute an American Muslim called Jeffrey Battle. Battle, a black man, had just been convicted of trying to go to Afghanistan to fight for the Taliban.
Armed, so they thought, with this arsenal of compromising detail, the Federal Prosecutor and the FBI had no patience with the pettifogging negativism of the Spanish police. So confident were the Americans of the guilt of their prey that they never went back to take another look at the supposedly matching prints. Instead, on April 21, they flew a member of the FBI’s latent print unit to Spain for on-the-spot refutation of the impertinent Madrid constabulary.
The Inspector General’s report makes it clear that the FBI man returned from Spain with a false account of his reception, alleging that the Spanish fingerprint team had bowed to his superior analytic skills. The head of the Spanish team, Pedro Luis Melida-Weda, insists that his team remained entirely unconvinced. “At no time did we give our approval. We refused to validate the FBI’s conclusions. We kept working on the identification.”
By now either the U.S. Attorney’s office or, more likely, the FBI was leaking to the press news of the pursuit of a U.S. suspect in the Madrid bombing. But they knew that the actual evidence they had on Mayfield was virtually non-existent, aside from the fingerprint. On May 6, the Federal Prosecutor in Portland told U.S. District Court Judge Robert Jones that the Spanish police had ultimately accepted the FBI’s match, that Mayfield, alerted by the stories in the press about an unnamed suspect, might start destroying evidence, and that, therefore, they wanted to seize Mayfield, using the now favored charge du jour of the war on terror, claiming him to be a “material witness”. Judge Jones approved an arrest warrant.
Mayfield had no idea that the FBI had been tapping his phones and secretly rummaging through his office. The first time he became aware that he was a citizen under suspicion was on the afternoon of May 6. On that day eight FBI agents showed up at his law office, seized him, cuffed his hands behind his back, ridiculed his protestations. As they approached the door, Mayfield implored them to take the handcuffs off, saying he didn’t want his clients or staff to see him in this condition. The FBI agents said derisively, “Don’t worry about it. The media is right behind us.”
Mayfield ended up with two federal public defenders, Steven Wax and Christopher Schatz. Like many such, these two were dedicated to their interest of their client, tireless and resourceful. Their first concern was to get Mayfield out of the Multnomah Federal Detention Center in downtown Portland. Though jailed under an alias chosen for him by the Federal Prosecutor, the feds had immediately leaked this alias–Randy Barker–to The Oregonian newspaper, and a guard at the jail had promptly roughed up Mayfield.
The two public defenders went before Judge Jones and asked that as a material witness he be kept under house arrest, there being scant apparent evidence against him. Judge Jones finally compelled the U.S. Prosecutor to say what evidence he had against Mayfield. A fingerprint, said the Federal Prosecutor, withholding from the court the fact that this fingerprint was highly controversial and had been explicitly disqualified by the Spanish police.
The federal defenders questioned the imprisonment of their client, faced penalties of the utmost gravity, on the basis of a fingerprint. Judge Jones allowed as how he had sent people to prison for life on the basis of a single fingerprint. Mayfield’s attorneys asked to see a copy of the allegedly matched fingerprints and have them evaluated by their own expert witness. Knowing he was on thin ice the Federal Prosecutor refused, claiming it was an issue of national security. Under pressure from Judge Jones, himself pressured by the assiduous federal defenders, the U.S. Prosecutor finally agreed he would give the prints to an independent evaluator selected by Judge Jones.
The prints were given to Kenneth R. Moses of San Francisco, an SFPD veteran who runs a company called Forensic Identification Services, which, among other things, proclaims its skills in “computer enhancement of fingerprints”. It was “quite difficult”, Moses said, because of “blurring and some blotting out”, but yes, the FBI had it right, and there was “100 per cent certainty” that one of the prints on the blue bag in Madrid derived from the left index finger of Brandon Mayfield.
Moses transmitted this confident opinion by phone to Judge Jones on the morning of May 19. Immediately following Moses’ assertion, the U.S. attorney stepped forward to confide to Judge Jones dismaying news from Madrid from the Spanish police that very morning. The news “cast some doubt on the identification”. This information, he added, “was classified or potentially classified”.
The prosecutors then huddled with the judge in his chambers. After 20 minutes, Judge Jones stormed back out and announced that the prosecutors needed to tell the defense lawyers what they had just told him. The prosecutor duly informed the courtroom that the Spanish police had identified the fingerprint as belonging to the right middle finger of Ouhnane Daoud, an Algerian national living in Spain. Daoud was under arrest as a suspect in the bombing. Judge Jones ordered Mayfield to be freed. The U.S. prosecutor said he should be placed under electronic monitoring, a request which the judge turned down.
Four days later, on May 24, the warrant for his detention was dismissed.
Continues at source.